docs: def _insert_vars(self, path: str, data: dict) -> str:
          """Inserts variables into the ESI URL path.
  
          Args:
              path: raw ESI URL path
              data: data to insert into the URL
  
          Returns:
              path with variables filled
          """
          data = data.copy()
          while True:
              match = re.search(self.VAR_REPLACE_REGEX, path)
              if not match:
                  return path
              replace_from = match.group(0)
              replace_with = str(data.get(match.group(1)))
              path = path.replace(replace_from, replace_with)